When is it permissible to operate a luminaire without a lens?

The operation of a luminaire without a lens is permissible only if the luminaire is specifically designed to function without one. This is because certain luminaires rely on their lens not only to protect the light source but also to ensure optimal performance, reduce glare, and distribute light effectively. Luminaires that are designed to operate without a lens typically have built-in protection, shielding, or other design elements that allow them to safely function without it.

Using a luminaire without a lens when it is not designed for that purpose can lead to various issues, including electrical hazards, exposure to the light source, or improper light distribution. Luminaires manufactured without a lens are constructed with this in mind, ensuring they can handle the conditions they'll face while operating safely and efficiently.